Power lift



I Oct. 24, 1944. w SILVER I 2,361,326

POWER LIFT Filed July 15, 1942 structural embodiment illustratediiri'the accom Figure 1 iso side view Patented Oct 24, 944 I PATENT orrics rowan LIFT Walter H. Silver, Mollne, 111., assignor to Deere &

' Company,

Moline, 111.,

a corporation of Illinois Application July 15,1942, Serial No. 451,067

Claims. (01. 91-50) v The present invention relates generally to agricultural implements and more particularly to power operated means for controlling the position of adjustable parts on the implement.

The object and general nature of the present 5 invention is the provision of a tractor-propelled implement having means to be adjusted, such as the tool or toolsto be raised and lowered, with hydraulic mechanism connected to adjust said adjustable means including conveniently operated means on'the tractor iorlimiting the movement of the implement adjusting means. More speciflcally, it is a feature of this invention to provide a source of pressure on the tractor'and a hydraulic. ram unit on the implement, with interstop means whereby to limit the operation of the a J ram'unit on the implement. 2 Another feature of this invention is the provision of a hydraulic system including a pair of seriallyconnected piston and 'cylinder units with means acting against the piston'of one unit for controlling the-movement .or operation of the serial NO 398 539 med June 1941 t which other unit. Another 'feature of this invention is the provision of interconnected hydraulic units, one adapted to be mounted on the tractor and the other on the implement,'with a flexible connection therebetween and with means associated with the unit on the tractor for controlling the movement of the unit on the implement. Still further, another ieatutre-oi-thisinvention is the provision of a hydraulic ram unit on an implement for adjusting one or more of the parts of. the latter, with means for operating the ram,

unit including a substantially constant volumeoi fluid serving as an operating connection between a source of power and; the ram unit, and a further for replenishing the confined body of fluidso as the same substantially constant p Theseand other objects and'advantages of the present invention will befapparent to those" skilled in the art after a consideration of the following detailed description; or fthe preferred panying drawing.

In the drawing:

plow, in which the principles of the present in-' I vention have been incorporated? Figure 2 is a fragmentary enlarged vertical section taken through the metering chamber; and

' mediate hydraulic means including a free piston, the movement of which is limited by adjustable Ali ing means for limiting the movement of the free piston in'the metering chamber. 1

Referring now to the drawing, particularly Figure 1, the reference numeral l indicates a tractor which is more or less of conventional construction and hence has been illustrated only trag mentarily. The tractor I includes rear drive wheels 2 fixed to drive axles 3 that are journaled for rotation in a rear axle housing 4. The latter is secured to or forms a part of a transmission hensing 5. The tractor l is equipped with a controlled source of fluid pressure, indicated in its entirety by the reference numeral 1 and which comprises a fluid pump 8 .driven from the shaft of the mechanism I!) which is actuated by a valve lever H. A fluid conduit in the form of a flexible hose connection l2 extends from the power unit I to a point of utilization to which reference will be 0 made in'more detail below. Thepresent invention is not especially concerned withl the particular details of the power unit I, the same beingpreferably of the-same construction as shown in the co-pending application of Jay D. Johnson,

30 fluidto be forced outwardly through the conduit 7 l2 under pressure and returning the lever II to neutral locks the fluid in the conduit l2 and associated connections. Depressing the lever H per- 1 from the hose connection I2 and the associated unitorunits.- v a K The tractor I is provided with'a drawbar l5 to which an agricultural implement, such as a traci l6, a g feature of this invention isthe provision oi means 0 tor propelled plow may be connected While the present invention is not necessarily limited to tractor-propelled.p1ows. this type of implement has been chosen so as best to indicate towed type and includes a pair or plow beams l1 to the lower rear ends of which plow bottoms ll are connected in the usualway. -The forward ends of the plow beams "are connected to a ver- 01 Gil ian-9 M1 -tical swingable hitchJndlcatd in itsfentirety by the referencenumeral 2|, which includes alone gitudinal draft member 23 and'a diagonal brace Y 24, to the rear-ends of both of whicha transverse bar, is connected. Draft brackets -28, are con- Figure 3 illustrates a modified form of'adjust nected to. the forward ends of the plowbeains l1 tractor governor 9 and suitable controlling valve;

mits fluid to flow freely back into the power unit ention. I Y,

' The plow l6'as illustrated is ,of the two-bottom 1 and are connected respectively by clevises 3] to the rear portion of the swingable hitch 2|. A drawbar extension 33 is bolted to the longitudinal member 23 and at its forward end receives a clevis 34 that is connected to the drawbar l5 of .the s tractor by a pivot pin 88.

A pair of crank axles 48 and 44 are journaled Q for rocking movement in brackets fixed to the plow beams ll and each crank axles includes a laterally turned end upon which a ground wheel, one of which is shown at 48, is mounted. The crank axles l3 and H are interconnected by suitable means so that they swing together, and an arm Si is fixed so that by swinging the arm both crank axles 43 and 44 are swung upwardly or downwardly so as to raise or lower the plow bottoms I8. I

The arms SI and associated crank axles 43 and 44 and other parts, which form a part of theimplement it, therefore forms implement means that is adapted to be adjusted, andthe adjustment of such means is eifected by means of a ramor cylinder and piston 'unit indicated in its entirety by. the reference numeral 80. The unit 60, together with the, other details of the implement and hitch, is shown and claimed in the co-pending application, Serial No. 427,541, filed January 21, 1942, by Frank T. Court, and 8. reference to this applicationmay be made if desired for a more detailed description of the parts. to

So far as the present invention is concerned, it is asensae -lar extensions; 88 and Qiand at its lowerend is threaded, as at Hi2, and at its .upper endpassesthrough the packing gland '89 and receives a hand wheel IN or other means by which the member l0! may be manipulated from the tractor seat S (Figure l) The operation of the mechanism so far described v other substantially incompressible fluid fills the cylinder 8| in front of the piston 62, the hose 86, the lower end of the metering chamber 15 below the piston 18, and the upper end of the metering chamber 15 and the hose I 2. The downward movement of the'free piston Hi therefore forces'an' ,amount of oil rearwardly through the hoseiit, acting'agaihst the piston 82 to extend the ram unit 88 on the implement it. In the modification shown, the piston 82 is anchored to a fixed-part 95 of the carrier 68 while the cylinder BI is connected at its forward end with a movable part of the carrier 86, that part be ing' the member indicated at 63a that is connected to and forms a partlofthe linkage 63. The forward movement of the cylinder 6| therefore re- I sults in swinging the arm 5| forwardly and raissufllcient to say that the ram unit 8|! includes .a

cylinder BI and a piston 62, the latter being connected by linkage ii3 withthe arm 5|. The unit ing thep lows i8 by swinging the crank axles 43 and 44 in a direction to raise the beams ll.

80 is supported on. the pivot pin 36 by a" carrier indicated in its entirety by the reference numeral 68. As best shown in said co-pending application,

the carrier 86 releasably supports the unit 60 so that in the event the pin 36 breaks the unit '80 ispulled away from the carrier 66 and out ofv connection with the linkage 8.3 automatically.

' Coming now to the feature with which the present invention is more particularly concerned, a cylinder and piston unit 10 is supported stationarily on the tractor l V in any suitable manner, the cylinder II, in the pre ferred form, being provided with attaching ears 12 which are apertured :to receive bolts or cap screws 13 for securing the cylinder H to the rear axle housing I as best shown in Figure l. The cylinder ll forms a metering chamber 15 in which a free piston 18' is movable. The piston 18, as best shown in Figure 2, comprises a supporting member 1'!- having a pair of leather cups [8 and 19 fastened by bolt 'means 8| to the'upper and lower side of-thesuplwrt II, with the lips of the leathersextending downwardly, as shown.

The lower end of the cylinder II is provided with a closure 82 in which an upwardly extending 6 stop 83 is disposed, the member 82 having a bored to move upwardly as oil flows back through the.

extension 84 which 'is threaded to receive the connection '85 at the forward end of a flexible hose section 88. The rear end of the hose 88 is con- As described above,.thevalve mechanism III is so arranged that when the lever H is returned to its neutral position fluid is hydraulically-locked in thesystem, including the hose l2 and the upper portion ofthe metering chamber 15. Since fluid is locked in this portion of the apparatus, it will be seen that the piston 62 will be held inits rearward position, relative to the cylinder 8|,with

the 'free piston 18 in a lower position in its cylinder H, such as is indicated in dotted lines in Figur 2, since it is the custom to raise the tools to the maximum raised position when transporting the implement.

The implement tools may be lowered by depressing the valve handle H, which releases the locked fluid 'in the upper portion of 'the metering chamber 15, whereupon the free piston 18 is free unit 1. This permits the piston 82 to move forwardly within its cylinder 8|, thus permitting the implement frame to lower. The movement of the tools" in this direction is limited by the free piston 16 engaging the lower end of the stop member II, which maybe turned to project its lower or inner end to a greater or lesser extent within the metering chamber 15. When 0 the piston 16 engages the pin "if, its movement is terminated, and since the piston 15 is no longer free to move, the other piston 82 is likewise held in; a hydraulically locked position. Thus. the

position ofthe adjustable stop member NH selivcs nected in any suitable manner with the .cylindfi 65 to adjust the position of the implement tools.

ii. The upper end ofthc cy nder carries a may therefore; be consideredthat the raising closure 9| which is provided with a slmilar bored and lowering of the tools is eflected by the extension 82 threaded to r c the real connectransmission of the force to'a first movable wall" tion 93 that formsapart of h ah' e hose 1. e., the piston is, which movement. is trans: l2 leading from the pressur n 7 i e 1) mitted by a combined body of substantially in- "*instmeaded, as at. as, an the'upper end .The upper closure 9! is provided with inner and outer tubular extensions 88 and 91, the former be,- ume to anothermovable wall, i. e., the piston 82,

movemenfiof which controls the tools, as delatter receiving a packinggland 88. An adjustscribed above.

abl stop member llil isdisposed within theitubu- It may occur, through "linkage and the like,

compressible fluid of substantiall constant vol-.

lusting pin shown in Figure 2.

. passage I3I with additional fluidpast the leathers and into the confined body of fluid. This may be accomplished by holding the valve II in its operating or pumping position after the piston I6 engages the stop 83. Such operation of the pump then in forcing fluid into the upper portion of the metering chamber I5 forces an equal amount past the leathers into the lower portion of the metering-chamber, thus replenishing any loss.

The leathers thus act as one-way valves, since being disposed inthe position shown flow of fluid upwardly past the piston I6 is prevented. Thus I have provided in a hydraulic system a convenient way for adjusting the lowered positions of the tool without in any way affectinge the action of the hydraulic mechanism in raising the tools to their fully raised position, entirely independent of whether or not the tools were adjusted for shallow or deep operation} In the preferred construction, turning the hand when the cylinder II is secured to thetractor in the same way as is shown in Figure 1. The reservoir I28 is adapted to contain asupply of fluidand communicates through a small opening I with the upper portion of the pump bore I32. In operation, the handle I31, is adapted to, be

operated, as by swinging the same in a counterclockwise direction about its supporting pivot M2,.

until the lower end of the pumpv plunger I passes upwardly beyond the opening I. Fluid .then flows into the lower end of the pump bore I32, whereupon-swinging the handle I31 in the other direction forces the pump plunger I35 downwardly, thus forcing oil past the check valve I33 and up the bore I3I into the adjusting pin cylinder I21. The adjusting pin I26 is therefore forced downwardly, as from its uppermost or dotted lineposition (Figure 3) an amount thatdepends upon the number of strokes given to the handle I31. The lower end of the-pin I26 constitutes a stop limiting the upward movement wheel I84 in one direction or the other adjustsv the pin IIII to vary the position atwhich the free piston IE will be stopped in its upward movement in the cylinder ,III. 'While in operating position,

it is a simple matter to unscrewthe member IIll to permit the piston 16 to move upward a slightamount, thus permitting the tools to lower a correspondingly slight amount. However, in order to provide for more shallow'operation', the

pin IIII would have to be rotated in the otherdirection, which means that the operator would have toturn the hand wheel vIll! against the weight of the tools and other parts. In the larger outfits, this may be inconvenient or diflicult, and

therefore in order to providea convenient way for adjusting the free piston stop in either directlon, either for more shallow. plowing or for deepamount.

ofthe free piston- I6 in substantially the same manner as the adjusting member IIII. shown in v Figure 2.

When it is desired, in the-construction shown in Figure 3,- to raise the lower end of the stop member; I28, the valve'le'ver II is moved downwardly so as to lower the tools until the piston I6 comes up against the lower end of the meme ber I26; Thecheckvalve I33 prevents any outward movement of the liquid into the pump bore I32, but the housing I20 is provided with a relief passage I-IG- which is controlled by a-ne'edle valve I41.- Opening the needle valve I41 therefore permits a flow, of fluid from above the upper end of the cylinder I21 and into the reservoir through a second relief .passage I49. In the construction shown in Figure 3, due to its hydraulic nature, it is a relatively simple matter. to force the adjustable member I26 downwardly, even through it results in manually raising the tools a slight While I have shown and described above the preferred structure in which the principles of the 45 present invention have been incorporatedit is to er plowing, the construction shown in Figure '3- may be substituted for thehand wheel and ad- ,dicated in its entirety bythe'reference numeral I20. The member I2ll' is'provided with a bored broader aspects of my invention.

- by Letters Patent is:

operator's station on the tractor, and a source offluid pressure driven by the tractor motor, theextension' I2I which communicates with the up per end of the metering chamber I5 and receives the high pressure hose I2 inthe same manner as is shown in Figures 1 and 2. The pump housing I20 forms a part of an adjusting hydraulic unit indicated in its entirety by the reference numeral I25. The unit I25 includes a stop member I26 the upper headed end of which serves as a piston that is movable within a small cylinder I21 formed in the pump housing I23. The latter also includes a reservoir I23, 'andthe upper end mmunlcates by means of a of the cylinder I21 co the lower end of a pump bore I32 past a check valve I33. Movable within the pump bore I32 is a pump plunger I35, the upper end of which passes out of the housing I20 and is connected, as at I38. with an operating lever I31. The upperv end of the lever I31 is disposed adjacent the operator's station s on the tractor be understood'that my invention is not -to' be limited totheparticular details shown and described above, but that, in fact, widely different means may be employed in the practice of the What I claim, therefore, and 1. In a tractor propelled implement adapted to =be connected with a tractor having a motor, an

combination of a cylinder adapted to be mounted on the tractor adjacent the operator's station and connected with said source of fluid pressure, a

no free piston movably mounted in said cylinder, a

ram unit adapted to be mounted on said implement and hydraulically connected with said cylinder, said cylinder having a volumetric capacity at least equal to the capacity of the cylinder of said ram unit whereby movement of said free piston in the cylinder through a single stroke operates the piston of said ram unit through a full stroke, means for controlling the flow of fluid under pressure to and from said source and said cylinder for shifting said free piston so as to shift said ram piston, and means for limiting the stroke of said free piston, said means" being accessible to an operatorat said operator's station, so as to limit the stroke of the piston of the ram unit on said implement.

desire to secure tion of a tractor, a source of fluid pressure thereon, an implement connected to the tractor for movement relative thereto and having a part to be raised, a single action ram unit mounted on saidimplement and including a movable element connected with said part for raising the latter when fluid under pressure is delivered to the cylinder or said ram unit to extend the same, a second cylinder mounted on the tractor and having a volumetric capacity at least equal to the volumetric capacity of said ram unit, a free piston movably mounted in said second cylinder, the

ends-of said last mentioned cylinder being closed,

a line leading from one end 01' said last mentioned cylinder to the cylinder'of said ram unit,

whereby movement of said 'free piston toward said as'enaac 2: In enagricultural implement, thelcomb inae said ram cylinder and acts by relative movement of the piston thereotto raise said implement part, controlling valvemeans for causing fluid to flowirom said source of fluid pressure into the other end of said second cylinder to move said free piston to said one end of the second cylinder and for causing fluid to flow out or said ram cylinder to permit said free piston to move toward the other end of said second cylinder so as to lower said implement part, and anadjustable stop adapted to be abutted by said free piston when moving toward said other end oi the second cylone end o'fJthe associated cylinder forces fluid an adjustable stop adapted to be abutted by said i'ree piston when moving toward said other end L of the second cylinder to limit the extent of lowering movement of said implement part.

'3. Inan agricultural implement, the combination of a tractor, a source of fluid pressure thereon, anlimplement connected to the tractor for movement relative'thereto and having a part to be raised, a single action ram unit mounted on inder to limit the extent oi. lowering movement 0! said implement part, said adjustable stop comprising a plunger extending into said other end of said second cylinder and a hydraulic pump for moving said plunger inwardly.

4. A metering cylinder for an agricultural'ram unit; comprising a chamber, a free piston therein.

a stop at each end extending generally axially inwardly, and means for adjusting the position of one of said stops, said adjusting means comprising a hydraulically actuated plunger, and release valve means therefor at the upper end of said cylinder.

5. In a tractor propelled implement adapted to be connected with a tractor having a motor, an

operator's station on the tractor,.and a source of fluid pressure driven by the tractor motor, the combination of a cylinder connected with said source of fluid pressure, a free piston movably mounted in said cylinder, a rain unit adapted to e be mounted on'said implement and hydraulically connected with said cylinder, said cylinder havsaid implement and including a movable ele- 1' ment connected with said part for raising the latter when fluid under pressure is delivered to the a cylinder of said ram unit to extend thesam'e, a second cylinder mounted on the tractor and hav- ,ing a free piston movably mounted therein, a line leading from one end of said lastmentioned cylinder to the cylinder of said ram unit, whereby movement of said free piston toward said one I end of the associated cylinder forces fluid into in a volumetric capacity at least equal to the capacity of the cylinder of said ram unit whereby movement of said free piston in the cylinder through a single stroke operates the, piston of said ram unit through a, full stroke, means for controlling the flow of fluid under pressure to and from said source and said cylimler for shifting saidfree piston so as to shift s id ram piston, and means disposed in a position accessible to an operator at said operator's station for iting the stroke of said free piston so as to it the stroke oi the piston of the ram unit on said implement,

' WALTER H. SILVER. 

